A variety of chemical and physical parameters of biological fluids are routinely analyzed in the diagnosis of disease and in routine monitoring of medical conditions. Many biological fluids must be processed prior to analysis to remove interfering proteins, biomolecules, or bulk properties of the sample. This can present difficulties in obtaining and validating the results obtained from biological sample analysis. Reliability and reproducibility of data is critical. Hence, simple sample preparation methods that yield accurate, reliable and reproducible results are highly desirable.
The sample preparation process has a direct impact on such analyses in terms of accuracy, precision, and quantitation limits. Effective sample preparation is extremely important to the analytical process. Optimally, the sample preparation process is relatively fast, easy, and an inexpensive means to obtain accurate and consistent results when analyzing a chemical or physical parameter of a biological fluid.
Non-invasive sample collection alternatives that reduce or eliminate the skin trauma, pain, infection risk and blood waste associated with traditional blood tests are also preferred.
Salivary diagnostics is an emerging field that relies on saliva as an easily-obtainable biological fluid for detection or diagnosis of various diseases and medical conditions. Unprocessed saliva is a viscous inconsistent fluid with unusual shear properties and which contains a number of proteins. These properties of saliva make it difficult to analyze bulk properties of saliva. Laboratory techniques such as solvent extraction, centrifuge filtration and/or relatively long periods of settling in sealed containers are often used to make saliva more amenable to subsequent analysis.
A noninvasive means to evaluate chemical or physical parameters of biological fluids, such as saliva, that is portable, simple, rapid to use, and which provides accurate, reliable and reproducible results is highly desirable. The present methods and systems address this need.